
package jweslley.ContestVolumes.VolumeCIV;

import java.util.Scanner;

import jweslley.Problem;
import jweslley.Problem.Status;

/**
 * http://icpcres.ecs.baylor.edu/onlinejudge/external/104/10469.html
 *
 * @author  Jonhnny Weslley
 * @version 1.00, 23/10/2008
 */
@Problem(Status.Accepted)
public class ToCarryOrNotToCarry {

	public static void main(String[] args) {
		StringBuilder out = new StringBuilder();
		Scanner in = new Scanner(System.in);
		while (in.hasNext()) {
			out
			.append(in.nextInt() ^ in.nextInt())
			.append('\n');
		}
		System.out.print(out);
	}

}
